Search found 177 matches
- 22 Feb 2024, 06:04
- Forum: ElmerSolver
- Topic: lagrangian element selection
- Replies: 7
- Views: 370
Re: lagrangian element selection
Thank you both for the detailed replies. There are indeed a lot of articles, books, and courses that deal with these isoparametric elements. Fortunately, my mesh elements have only straight edges. It is very refined around a curved airfoil so that I don't think it matters if it follows the curved ar...
- 19 Feb 2024, 01:36
- Forum: ElmerSolver
- Topic: lagrangian element selection
- Replies: 7
- Views: 370
Re: lagrangian element selection
Actually, what spurred my post was an article entitled Fluid Modelling of Dielectric Barrier Discharges for Plasma Technology by Jovanovic et al. Their research uses Comsol and in a given domain, they have linear Lagrange elements for continuity equations and quadratic Lagrange elements for the Pois...
- 15 Feb 2024, 00:37
- Forum: ElmerSolver
- Topic: lagrangian element selection
- Replies: 7
- Views: 370
lagrangian element selection
Hi Let's say I have a given triangular mesh (generated by Gmesh and transformed by ElmerGrid into the ElmerSolver format) How do I setup a given solver in the SIF to use linear Lagrange elements and another one to use quadratic Lagrange elements ? Also how would I tell a solver to use discontinuous ...
- 28 Jan 2024, 07:00
- Forum: ElmerSolver
- Topic: upwind or central difference scheme ?
- Replies: 1
- Views: 281
upwind or central difference scheme ?
Good evening The finite volume method usually use upwind scheme for convection terms and central difference scheme for diffusion terms. I know that the finite element method adopted the same idea since the late 1970s. I was curious to know if the same is true of the Elmer software because I don't se...
- 17 Jan 2024, 23:48
- Forum: ElmerSolver
- Topic: operator splitting and time integration schemes
- Replies: 1
- Views: 257
Re: operator splitting and time integration schemes
I got astronomical overflows after only 3e-8 sec for explicit euler and after only 6.5e-8 sec for implicit euler
I guess Elmer doesn't like my 3 ion continuity equations
I guess Elmer doesn't like my 3 ion continuity equations
- 16 Jan 2024, 06:05
- Forum: ElmerSolver
- Topic: operator splitting and time integration schemes
- Replies: 1
- Views: 257
operator splitting and time integration schemes
Good evening
If I decompose a PDE into a sequence of
dF/dt = some homogeneous term
dF/dt = some reaction term
should I use an an implicit or explicit time discretization scheme for each of these simplified PDEs ?
Best to all
If I decompose a PDE into a sequence of
dF/dt = some homogeneous term
dF/dt = some reaction term
should I use an an implicit or explicit time discretization scheme for each of these simplified PDEs ?
Best to all
- 16 Jan 2024, 03:02
- Forum: General
- Topic: Time discretization schemes
- Replies: 7
- Views: 4315
Re: Time discretization schemes
I found out that
you keep write
Timestepping Method = runge-kutta
inside a solver section
but there are implicit Runge Kutta methods. I am not sure if the default is explicit in Elmer. Also I wanted to set it to lowest order - just a simple Euler iteration.
you keep write
Timestepping Method = runge-kutta
inside a solver section
but there are implicit Runge Kutta methods. I am not sure if the default is explicit in Elmer. Also I wanted to set it to lowest order - just a simple Euler iteration.
- 14 Jan 2024, 18:04
- Forum: General
- Topic: Time discretization schemes
- Replies: 7
- Views: 4315
Re: Time discretization schemes
Hello
I know Crank Nicholson is half explicit and half implicit. BDF first order is fully implicit.
So what keyword setting should I use in a solver section to make its time integration fully explicit ?
Thanks
I know Crank Nicholson is half explicit and half implicit. BDF first order is fully implicit.
So what keyword setting should I use in a solver section to make its time integration fully explicit ?
Thanks
- 09 Jan 2024, 20:16
- Forum: ElmerSolver
- Topic: My advice on computational speed
- Replies: 8
- Views: 1093
Re: My advice on computational speed
Maybe I have not recovered from the cold yet. Not thinking straight - forgot to supply the mesh. Here it is attached with the previously reported code. Frankly, not sure what you mean by Hardcoded constant value , "Equals" and F90. In the end, I don't think I will use GetElementNodesVec. T...
- 08 Jan 2024, 00:37
- Forum: ElmerSolver
- Topic: My advice on computational speed
- Replies: 8
- Views: 1093
Re: My advice on computational speed
Hello in the following very simple test, the handles are initialized only once. Just compile SoSimpleTest and run the two SIFs. You will observe from the output of CheckTimer that the material coefficient reading a field variable using Real MATC "tx(0)" yields a time value that is about 40...